code: def _flags_src_ext(src):
      ext = os.path.splitext(src)[1].lower()
      if ext == ".in":
          return _flags_src_ext(src[:-3])
      return ext
  
imports: import logging
  import os
  from guild import guildfile
  from guild import op_util
  from guild import plugin
  from guild import util
  from .None import flags_import_util
label_desc: Use image node_id 5 for calling a global function with example usage: _flags_src_ext(src) and returns: ext, _flags_src_ext